public void InsertRange(int index, ReadOnlySpan <T> items)
{
lock (SyncRoot)
{
using (var xs = new CloneCollection <T>(items))
{
list.InsertRange(index, xs.AsEnumerable());
CollectionChanged?.Invoke(NotifyCollectionChangedEventArgs <T> .Add(xs.Span, index));
}
}
}
public void AddRange(IEnumerable <T> items)
{
lock (SyncRoot)
{
var index = list.Count;
using (var xs = new CloneCollection <T>(items))
{
// to avoid iterate twice, require copy before insert.
list.AddRange(xs.AsEnumerable());
CollectionChanged?.Invoke(NotifyCollectionChangedEventArgs <T> .Add(xs.Span, index));
}
}
}
